Preoperative Detection of Cerebral Motor Areas by Functional MRI: Feasibility of Functional Arterial Spin Labeling (fASL) and Comparison to Blood Oxygenation Level Dependent Technic (BOLD), Anglais

Résumé du livre

Goal : Our goal was to evaluate fASL feasibility for Primitive Motor Area (PMA) detection in clinical context of pre-operative planning of brain tumors. Materials and methods : Imaging was performed at 3T with a 32-channel coil using block paradigms. The task was thumbs-todigit oppositions at 1Hz of the contralateral hand to the lesion. BOLD acquisitions and pseudocontinuous ASL acquisitions with Post Labeling Delay of 1500ms (pCASL1500) and 1000ms (pCASl1000) were performed on 21 subjects (4 healthy volunteers and 17 patients). For both fASL and BOLD techniques, motor maps were produced using a General Linear Model (GLM) and a massively univariate statistical analysis with a Family Wise Error Rate of 5 %. Detection rate was evaluated visually. It was defined by the percentage of subjects, whose motor map visually overlapped the PMA (PMA was defined by anatomical landmarks). The spatial accuracy of the PMA positioning by functional MRI was evaluated using manual segmentation of PMA as reference Region Of Interest (omega ROI): Sensitivity, specificity, predictive positive and predictive negative value of the omega ROI detection were performed. An analysis ROI centered on central region was defined to contain the calculations and overcome inter-patient variability in other motor area activation. Activation volumes were finally calculated to compare them to omega ROI volumes. Results : Detection rates by visual evaluation were 47.6 % for pCASL1500, 85.7 % for pCASL1000 and 95.2 % for BOLD. Detection sensitivity of the omega ROI was significantly higher in BOLD (80.6 ±26%) compared to pCASL1500 (19 ± 32 %, p